This invention relates to a ladder leveling apparatus and, more particularly, to such a leveling apparatus which assures the stable support of a ladder on an uneven surface with minimal attention on the part of the one using a ladder equipped with the invention.
Ladder leveling devices of the type by which one or both side rails of a multi-rung ladder are made extensible at their lower ends to accommodate support of the ladder on an uneven or irregular surface are exemplified by the disclosures of U.S. Pat. Nos. 1,329,740, 1,223,367, 2,449,609, 2,147,052, 2,327,317 and 4,807,720. The ladder leveling devices of the prior art generally require physical manipulation of the device at the lower end of the ladder independent of orienting the ladder in a vertical plane. The procedure by which the leveling device is adapted to an uneven support involves a substantial measure of trial and error manipulation of both the leveling device and the ladder with which it is assembled. Where a single person is attempting to adjust such devices on rather long ladders, &he procedure for achieving a true stable support can become tedious.
There is a need, therefore, for a ladder leveling device which is self-adjusting to an irregular supporting surface as a result of manipulation only of the ladder so that once the ladder is oriented in a vertical plane, the leveling device on which the ladder is supported is simply fixed to retain the ladder with stability in the properly oriented position.